As some have said, the "tithe" was an elelment of the Old Covenant law. It was in part how ancient Israel worked. And many have tried to impose the "tithe" upon the church; and as part of such an imposition, they have tried to make those who don't "tithe" feel quilty. Please realize that there is a difference between giving and "tithing". The tithe was an Old Testament commandment; giving from the heart has always been acceptable to God. The church operates under the New covenant, and there is no place in the New Testament where the tithe is commanded of those in the church.
Now, giving is both good and commanded, but the amount is up to you, and what you are able to give. Don't let those who misunderstand the tithe, and try to play the guilt card on you, make you feel guilty about how much you give. Such persons are just like those that tried to compel people to get circumcised. They want to lead you into legalistic bondage. God wants you to give, but first one must pay his essential bills and support his family. After that, then one should give from what is left. Remember, giving should be from the heart and not by compulsion. If you are being compeled to tithe, then you are being misled. Avoid such persons.